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Comment: Another SanDiegoFire memory (Score 1) 36

by calidoscope (#48660707) Attached to: How a Wildfire Helped Spread the Hashtag
One of the most useful instances of social media and Googles apps was a series of postings on a San Diego Union Tribune discussion board related to the fires. The poster was embedding links to a Google Maps page with frequently updated fire perimeter along with reports of where the evacuation centers were being set up. It was very useful as my family and I were about an hour from needing to evacuate when the winds shifted.

Comment: Re:the law (Score 1) 145

by calidoscope (#48477297) Attached to: Scientists Develop "Paint" To Help Cool the Planet

"it becomes cooler than the surrounding air by around 9F (5C)"

Sorry, not possible, as per the first law of thermodynamics.

How in the hell do you think dew gets deposited on grass, cars, etc? Dew forms when the surface temperature drops below the dew point of the air, which cannot be any higher than the ambient air temperature.

FWIW, a problem from my engineering heat transfer course indicated that frost can form when the air temp is 9F/5C above freezing.

Comment: Re:Wired Access Will Still Be Standard (Score 1) 99

by calidoscope (#48201715) Attached to: Internet Broadband Through High-altitude Drones

And fiber has even more bandwidth than copper.

Your point is correct about fixed links providing far more bandwidth that what can be provided by any kind of wireless link. The drone concept only make sense in places like the lightly populated areas of the US or similar countries where customers are too far apart to make wireline or fiber communications affordable. The low altitude with respect to satellites means that the link frequencies can be re-used more frequently.

Comment: Sunjammer was the orignal title (Score 1) 74

by calidoscope (#48182679) Attached to: NASA Cancels "Sunjammer" Solar Sail Demonstration Mission
I remember one of my brother's first issues (Apr? 1964) of Boy's Life having "Sunjammer" as the cover story. AC Clarke later expanded the story under the name "Wind from the Sun". FWIW, Boy's Life is one of the magazines digitized by Google Books and you can look up the issue in question.

Comment: Re:Article ignores variability (Score 1) 610

by calidoscope (#48136959) Attached to: Wind Power Is Cheaper Than Coal, Leaked Report Shows

Actually, you're the one who comes across as being ignorant.

Baseload generation is generation is considered to be the lowest incremental cost dispatchable power source. No form of generation has 100% up time, but a well run plant will have very little unscheduled down time. The variability of wind is a huge problem when wind generation becomes a significant portion of total generation at a give moment, requiring a large amount of spinning reserve to keep the grid stable.

FWIW, the limiting factor in power output of an AC generator is not conductor heating, rather it is the amount of power that can be generated without the generator pulling out of synchronism, especially under fault conditions.

Comment: The Power Makers by Maury Klein (Score 2) 140

by calidoscope (#48124867) Attached to: Ask Slashdot: Best Books On the Life and Work of Nikola Tesla?

While this book is not a Tesla biography, it does give a good picture of how Tesla fit in with the beginnings of the electric power industry. The book does give Tesla proper credit for the invention of poly-phase AC and the induction motor, but also points out that Stanley and Thomson were working on AC distribution before Tesla along with a lot of refinement on the induction motor being done by Benjamin Lamme.

It is the likes of Lamme and Steinmetz that are the unsung heroes of the electrical age.

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